Portable ladder for a manhole or the like



Dec. 20, 1960 c. F. PAscHEN 2,965,195

PORTABLE LADDER FOR A MANHOLE 0R THE LIKE Filed April 25, 1959 IN V ENTOR.

PORTABLE LADDER FOR A MANHOLE R THE LIKE Clayton F. Paschen, 2739 ElstonAve., Chicago 47, Hl.

Filed Apr. 23, 1959, Ser. No. 808,420

3 Claims. (Cl. 182-206) This invention relates to improvements in aportable ladder for street manholes, sewers and the like, and refersparticularly to a portable ladder which may be made in identical unitsso contrived that a unit ladder or a plurality of units may be employedto gain access to the bottoms of street manholes, sewers or the like ofvariable depths.

One of the objects of the present invention resides in a ladderconstruction so contrived as to be quickly and conveniently applied tothe inner wall of a street manhole, sewer or the like to gain access tothe bottom thereof.

Another important object of the invention resides in a ladderconstruction which can be made in identical units and which can be usedas a single unit or used in a plurality of cooperating units as thedepth of the manhole or sewer requires.

A further important object of the invention resides in a unit ladderwhich may be made of strong light-weight material such as aluminum orthe like and can be easily and conveniently transported from place toplace.

Other objects and advantages of the present invention will be apparentfrom the accompanying drawing and following detailed description.

In the drawings,

lFig. l is a top plan view of a manhole or sewer with a ladder,embodying the concepts of the present invention, secured to the innerwall thereof.

Fig. 2 is a longitudinal sectional view through the walls of a manholeor sewer taken on line 2 2 of Fig. l.

Fig. 3 is a detailed sectional View taken on line 3-3 of Fig. 2.

Fig. 4 is a detailed sectional view taken on line 4-4 of Fig. 2.

Fig. 5 is a detailed elevational view looking in the direction of thearrows 5 5 of Fig. 4.

Fig. 6 is a detailed sectional View taken on line 6-6 of Fig. 3.

Referring in detail to the drawing, 1 indicates generally a conventionalmanhole or sewer, the manhole or sewer being dened by cylindricalsections 2. The sections 2 are preferably made of precast concrete,molded clay tile or the like and all sections are similar and nest orinterit to define a manhole or sewer of desired depth.

The wall of each section at one end is provided with an annular notch 3,the inner wall 4 of the notch being tapered to form a male annularprojection 5. The wall of the opposite end of each section isreciprocally formed, having an outer annular projection 6 dening aninner annular female recess 7 into which the projection 5 of theadjacent section interiits. The sections 2, hereinbefore described, areconventional and per se form no part of the present invention.

However, to adapt such conventional sections to use in the presentinvention, the sections must be slightly modified. The modificationsimply consists in providing a pair of spaced axial slots 8 in the edgeof one end of each section wall. These notches may be provided dur-2,965,195 Patented Dec. 20, 1960 ing the manufacture of the sections orthey may be cut or chiseled in the cylindrical sections of preexistingmanholes or sewer installations.

Ladder 9 comprising an embodiment of the invention comprises a pair ofspaced rails 10 which carry spaced rungs 11. At one end of the ladder,the rails are disposed transversely to the major length of the rails toform parallel attaching members 13 which at their ends carry hookelements 14. Intermediate each attaching member 13 a pin 15 is rigidlycarried, said pin preferably extending through the attaching member, butat all events extending above and below the attaching member. The pin 15is spaced from the hook element 14 a distance slightly greater than thethickness of the wall of the section 2.

At the opposite end of each ladder unit 9, the rails 19 terminate infeet 16 which extend parallel to each other transversely to the majorlength of the rails and are, in eiect, continuations of the rails. Eachfoot intermediate its length is provided with an aperture 17. As will behereinafter more fully described, the apertures 17 in the feet 16 arefor the reception of the extending end portions of pins 15 when multipleunits of the ladder are employed.

In employing the ladder 9, the attaching members 13 may be positionedthrough the slots 8, the section 1G being inserted in the manhole orsewer, and the hook elements 14 may overlie the outer face of thecylindrical member 2. ln this position the p-ins 15 will overlie theinner face of the member 2 and radial or inward or outward movement ofthe attaching members 13 relative to the cylindrical wall of the manholeor sewer will be prevented.

The feet 16 will be disposed adjacent the bottom of the member 2 if thedepth of the manhole or sewer only requires one cylindrical member 2.

ln most instances, however, the depth of the manhole or sewer will besuch as to require a plurality of cylindrical members 2. in this case,the cylindrical members are positioned end to end in nested fashionwherein the projection 5 of a lower member 2 will intert with theannular groove 7 of an upper member. The members 2 are so positionedthat the slots 8 of the superimposed members are in substantial verticalalignment. In this position, the feet 16 of an upper ladder section 1Gare positioned in the slots 8 of a lower cylindrical member 2, and theattaching members 13 of a lower ladder section are also positioned insaid same slots, the feet of the upper ladder section being superimposedabove the attaching members 13 of the lower ladder section. In thisposition pins 15 of the attaching members 13 of the lower ladder sectionwill be engaged in the apertures 17 of the feet of the upper laddersection. The hook elements 14 of the attaching members 13 of the lowerladder section will engage the outer face of the lower cylindricalmember 2 and pins 15 carried by the attaching members 13 will engage theinner face of the wall of the lower cylindrical member 2 to preventundesirable movement of the lower ladder section and also to preventsuch undesirable movement of the lower end of the upper ladder section.

As many ladder sections 1th as desired may be similarly intertted toprovide a ladder 9 of a length appropriate to the depth of the manholeor sewer.

As an advantage, the ladder sections may be applied, in the mannerdescribed, from the top of the manhole or sewer, downwardly, and may beremoved from the bottom upwardly.

1f desired, the unit ladder or a ladder comprising a plurality ofsections may be employed as a permanent installation in the manhole, inwhich case, after the ladder has been installed, as hereinbeforedescribed, the

apertures or slots in the manhole wall may be lled with a suitablegrout.

The function of the pins 15 is to contribute stability of the laddersections with respect to the manhole or sewer wall and with respect toeach other. Such pins may be supplanted by other obvious equivalentssuch as lugs or washers or each attaching member 13 may carry a pin atits lower edge and be provided with an aperture at its upper edge andeach foot may carry a pin at its lower edge which would, at the junctureof the ladder sections, engage in the aperture in the correspondingattaching member. These and` other modifications are broadlycontemplated in the present inven tion and it is not intended that theinvention be limited to the exact details shown and described, except asnecessitated by the appended claims.

I claim as my invention:

1. A portable ladder for a manhole dened by a wall provided with a pairof spaced slots, said ladder comprising spaced parallel rails, spacedrungs carried by said rails, an attaching member carried at acorresponding end of each rail, said attaching member being disposedtransversely to the length of said rail for positioning in a respectiveslot in said manhole wall, a hook element carried at the end of eachattaching member for overlying engagement with the outer face of saidmanhole wall, a rigid abutment carried intermediate the length of eachattaching member extending above and below same for overlying engagementwith the inner face of said manhole wall, and a foot provided with anaperture intermediate its length carried at the opposite end of eachrail and extending transversely to the length of said rail insubstantially parallel relationship to said attaching members, saidaperture being spaced from the rail equidistant to the abutment carriedby the attaching member.

2. A portable ladder for a manhole deiined by a wall provided with pairsof spaced slots, said ladder comprising a plurality of ladder sections,each section comprising spaced parallel rails, spaced rungs carried bysaid rails of each ladder section, an attaching member carried at acorresponding end of each rail of each ladder section, each attachingmember being disposed transversely to the length of said rail forpositioning in a respective slot in said manhole wall, a hook elementcarried at the end of each attaching member for overlying engagementwith the outer face of said manhole wall, a rigid abutment carriedintermediate the length of each attaching member extendingabove andbelow same for overlying engagement with ythe inner face of said manholewall, and a foot provided with an aperture intermediate its lengthcarried at the opposite end of each rail of each ladder section andextending transversely to the length of said rail in substantiallyparallel rela tionship to said attaching members for extending into arespective slot provided in the adjacent manhole wall, said aperturebeing spaced from the rail equidistant to the abutment carried by theattaching member.

3. A portable ladder for a manhole defined by a wall provided with pairsof spaced slots, said ladder comprising a plurality of ladder sections,each section comprising spaced parallel rails, spaced rungs carried bysaid rails of each ladder section, an attaching member carried at acorresponding end of each rail of each ladder section, each attachingmember being disposed transversely to the length of said rail forpositioning in a respective slot in said manhole wall, a hook elementcarried at the end of each attaching member for overlying engagementwith the outer face of said manhole wall, a rigid abutment carriedintermediate the length of each attaching member extending above andbelow same for overlying engagement with the inner face of said manholewall, and a foot provided with an aperture intermediate its lengthcarried at the opposite end of each rail of each ladder section andextending transversely to the length of said rail in substantiallyparallel relationship to said attaching members for extending into arespective slot in the adjacent manhole wall, said aperture being spacedfrom the rail equidistant to the abutment carried by the attachingmember, and means carried by each abutment engaging in the aperture ofeach foot which extends into said respective slot.

References Cited in the le of this patent UNITED STATES PATENTS 236,044Krause Dec. 28, 1880 334,237 Ketchum Ian. l2, 1886 1,436,138 AndersonNov. 2l, 1922 1,712,510 Monie May 14, 1929 1,944,384 West lan. 23, 19342,126,218 Schulz Aug. 9, 1938

